New Fiber Optic Technology Conquers the Bandwidth Bogdown

A team of scientists may have just solved our massive bandwidth issue, allowing us to keep our internet filled with cat videos for decades to come.

See, as more of the country gets connected and streams video from their cousin's friend's Netflix accounts on their iPads, phones, PS3s, and computer all at the same time, the fiber optic infrastructure can get bogged down. In the past, this wasn't a problem—when telecom companies wired a community with fiber, typically less than 10 percent of its total available bandwidth was used. Whenever a new customer signed up, they added in a new data transmitter and receiver, which beamed a slightly different color light than yours, keeping your Metallica torrents separate from the Britney Spears ones your neighbors kid was using.

But increasingly, we're running out of colored beams of light: As you fill up a fiber optic cable with different colors, they get closer and closer together, eventually creating a phenomena known as nonlinear distortion, says Siddharth Ramachandran, a Boston University researcher and lead author of the paper, published in Science.

Well, now instead of beaming the light in straight lines, we can beam it in a tornado-like shape, known as orbital angular momentum. It's a technology that researchers have been working on for a while, but until recently, we couldn't pull it off in anything longer than a one meter cable. Not anymore.

An international team of researchers and commercial fiber companies have successfully sent and received data through a one kilometer fiber specially designed to use OAM, allowing them to transmit 1.6 terabits of data a second, roughly eight Blu-Rays' worth.

"A few years ago, people in our community got together and saw this exponential growth of bandwidth demand and the slow growth of fiber. They weren't matching up. Service providers can put in more fiber optic lines, but that's a linear process, it's not exponential growth," Ramachandran said. "We've added another degree of freedom to these fibers."

Each shape of light, or "mode" allows additional data flow to go through the same cable--think of it as instead of sending a bunch of straight steel rods through the cord, they're sending corkscrewed, flexible ones, allowing them to pack more into each fiber.

The next step is to see if OAM fibers can successfully transmit data over longer distances--sometimes they have to be thousands of miles long. The fact that the data made it successfully for a kilometer is a good sign, considering all previous tests failed within a few inches or feet. But even at less than a kilometer, the fiber has a good application for companies with huge server farms, such as Facebook and Google.

"We're not sure if it'll work for long haul networks, but data communications potentially has an even bigger bottleneck on server farms," Ramachandran said. "A lot of the communication between those servers is done with fiber right now, and they're hurting on how to figure out how to keep up with the massive amounts of data that needs to be sent from one chip to another. This could potentially do that."

For now, it's anyone's guess whether OAM will lead to a faster overall experience for users. But it should, in theory, allow many more people to connect through the same fiber optic line without the bandwidth slowdown a lot of internet users are seeing. OAM lines won't replace existing lines, but newly-laid lines could complement them, Ramachandran said.

And unlike lots of fancy new research, this one is all but ready for use. One of the researchers involved in the project was Poul Kristensen, of OFSFitel, one of the world's largest fiber optic cable manufacturers. Ramachandran said that the OAM cables were created on OFSFitel's production floor.

"We're not just doing this for fun," he said. "This is actually production fiber. Service providers know they'll eventually have to do a next generation fiber run, the question is, should they start putting in new kinds of fiber?"

Ramachandran thinks they can.